Houses and other structures are constantly subjected to damage caused by factors such as, for example, insects, pests, fungi, and excess moisture. Indeed, such factors may even pose a risk to the well-being for the inhabitants. Inspections for damage caused by these and other factors are typically conducted manually at either regular intervals or on an as-needed basis. Manual inspections, however, are often costly because inspectors must be present at the site. Moreover, manual inspections of this nature may prove to be quite invasive, insofar as inaccessible or otherwise remote portions of a given structure may require significant disturbance to walls, ceilings, etc., thereby resulting in added inconvenience and expense. Further, if the manual inspections are not conducted in a timely fashion, severe damage to the structure may have already occurred by the time the damage is revealed through a manual inspection. This can be especially true if the damaging factor is subterranean termites.
Subterranean termites most often enter structures from the surrounding soil to feed on wood, or other cellulosic material, of the structure and its contents. If unchecked, termites can cause considerable damage. As a result, efforts to erect physical or chemical barriers to prevent the entrance of termites into a structure or to exterminate the termites after they have invaded a structure have proven a considerable expense to the public (Su, N.Y., J. H. Scheffrahn [1990] Sociobiol. 17(1):77-94). The cost to control termites in the United States exceeds one billion dollars annually (Mauldin, J. K. S. C. Jones, R. H. Beal [1987] The International Research Group on Wood Preservation Document No. IRG/WP/1323).
Subterranean termites construct an extensive foraging gallery beneath the soil surface. A single colony may contain several million termites with foraging territory extending up to 300 feet (Su, N. Y., R. H. Scheffrahm [1988] Sociobiol 14(2):353-359). Since Subterranean termites are a cryptic creature, their presence is not normally known until after some damage, foraging tubes, or live termites such as swarmers, are found. Some subterranean termites are known to forage beneath an object on the soil surface (Ettershank, G., J. A. Ettershank, W. G. Whitford [1980] Environ. Entomol 9:645-648).
Certain methods and apparatuses have been suggested to monitor for and control pests such as subterranean termites. For example, International Publication No. WO 93/23998 (Dec. 9, 1993) discloses methods and materials for pest management which include a series of connected monitoring blocks that are placed in soil adjacent to and surrounding a structure foundation. A thin strip of conductive metal is embedded in each monitoring block such that a contiguous circuit is formed by the connected monitoring blocks. Severe infestation by termites in the monitoring block results in the breaking of the contiguous circuit, which can be registered by an electronic device. Despite its many advantages, however, an arrangement of this sort can be relatively cumbersome in particular applications. This arrangement also requires the presence of a technician to conduct on-site monitoring. Moreover, since the point of circuit breakage cannot be readily isolated, it sometimes may be difficult to promptly determine the precise location of sensed termites.
It is therefore highly desirable to more efficiently and effectively monitor for biotic and abiotic factors, such as insects and other pests, fungi, and excess moisture, so as to minimize damage that may be caused by such factors. It is especially desirable to more efficiently and effectively monitor for the presence of subterranean termites.
Other objects and advantages of the present invention will be apparent to those of skill in the art, based upon the figures and the following description.